iOS Quickstart

Objective-C Swift

The steps described on this page explain how to quickly create a simple iOS application that makes requests to the YouTube Data API. This sample shows how to retrieve data about the GoogleDevelopers YouTube channel. The code also includes comments that explain how to modify the query to retrieve data about the current user's YouTube channel.

Note: The application does not conform with Apple's iOS Human Interface Guidelines. It is intended only to illustrate the basic concepts and steps needed to begin working with the YouTube Data API.

Prerequisites

To run this quickstart, you'll need:

• Xcode 8.0 or greater.
• CocoaPods dependency manager.
• Access to the internet and a web browser.
• A Google account.

Step 1: Turn on the YouTube Data API

1. Use this wizard to create or select a project in the Google Developers Console and automatically turn on the API. Click Continue, then Go to credentials.

2. On the Create credentials page, click the Cancel button.

3. At the top of the page, select the OAuth consent screen tab. Select an Email address, enter a Product name if not already set, and click the Save button.

4. Select the Credentials tab, click the Create credentials button and select OAuth client ID.

5. Select the application type iOS, enter the name "YouTube Data API Quickstart", bundle ID com.example.QuickstartApp, and click the Create button.

Step 2: Prepare the workspace

Note: All of the examples are based on the name com.example.QuickstartApp. If you named your app something other than that, like com.example.QuickstartYTApp, change the string QuickstartApp to match your app name.

1. Open Xcode and create a new project:
   1. Click File > New > Project, select the iOS > Application > Single View Application template, and click Next.
   2. Set the Product Name to "QuickstartApp", Organization Identifier to "com.example", and Language to Swift . Below the organization identifer, you should see a generated Bundle Identifier that matches the iOS Bundle ID (com.example.QuickstartApp) that you entered in step 1.b.
   3. Click Next.
   4. Select a destination directory for the project and click Create.
2. Close the project by clicking File > Close Project.
3. Open a Terminal window and navigate to the directory that contains the QuickstartApp.xcodeproj file you just created.

4. Run the following commands to create the Podfile, install the library, and open the resulting XCode project:

   cat << EOF > Podfile &&
   platform :ios, '8.0'
   use_frameworks!
   target 'QuickstartApp' do
       pod 'GoogleAPIClientForREST/YouTube', '~> 1.2.1'
       pod 'Google/SignIn', '~> 3.0.3'
   end
   EOF
   pod install &&
   open QuickstartApp.xcworkspace
   

5. In the XCode Project Navigator select the project node "QuickstartApp". Then click the menu item File > Add files to "QuickstartApp".

   

6. Locate the GoogleService-Info.plist file downloaded earlier and select it. Click the Options button.

   

7. Make the following selections in the options window and then click the Add button:

   1. Check the Copy items if needed checkbox.
   2. Check all targets listed in the Add to targets section.

   

8. With the project node still selected, select "QuickstartApp" in the TARGETS section as shown in the two images below:

   1. Click the area shown in this screenshot:

   2. Then select the proper target:

9. Select the Info tab, and expand the URL Types section.

10. Click the + button, and add a URL scheme for your reversed client ID. To find this value, open the GoogleService-Info.plist configuration file that you selected in step 2.f. Look for the REVERSED_CLIENT_ID key. Copy the value of that key, and paste it into the URL Schemes box on the configuration page. Leave the other fields blank.

11. Rebuild the project:

    1. Click Product > Clean Build Folder (while holding the option key).
    2. Click Product > Build.

Step 3: Set up the sample

Replace the contents of the following files with the code provided:

AppDelegate.swift

import GoogleSignIn
import UIKit

@UIApplicationMain
class AppDelegate: UIResponder, UIApplicationDelegate {

    var window: UIWindow?

    func applicationDidFinishLaunching(_ application: UIApplication) {
        // Initialize Google sign-in.
        GIDSignIn.sharedInstance().clientID = "<YOUR_CLIENT_ID>"
    }

    func application(_ application: UIApplication,
                     open url: URL, sourceApplication: String?, annotation: Any) -> Bool {
        return GIDSignIn.sharedInstance().handle(url,
                                                 sourceApplication: sourceApplication,
                                                 annotation: annotation)
    }

    @available(iOS 9.0, *)
    func application(_ app: UIApplication, open url: URL,
                     options: [UIApplicationOpenURLOptionsKey : Any]) -> Bool {
        let sourceApplication = options[UIApplicationOpenURLOptionsKey.sourceApplication] as? String
        let annotation = options[UIApplicationOpenURLOptionsKey.annotation]
        return GIDSignIn.sharedInstance().handle(url,
                                                 sourceApplication: sourceApplication,
                                                 annotation: annotation)
    }

}

ViewController.swift

import GoogleAPIClientForREST
import GoogleSignIn
import UIKit

class ViewController: UIViewController, GIDSignInDelegate, GIDSignInUIDelegate {

    
    // If modifying these scopes, delete your previously saved credentials by
    // resetting the iOS simulator or uninstall the app.
    private let scopes = [kGTLRAuthScopeYouTubeReadonly]

    private let service = GTLRYouTubeService()
    let signInButton = GIDSignInButton()
    let output = UITextView()

    override func viewDidLoad() {
        super.viewDidLoad()

        // Configure Google Sign-in.
        GIDSignIn.sharedInstance().delegate = self
        GIDSignIn.sharedInstance().uiDelegate = self
        GIDSignIn.sharedInstance().scopes = scopes
        GIDSignIn.sharedInstance().signInSilently()

        // Add the sign-in button.
        view.addSubview(signInButton)

        // Add a UITextView to display output.
        output.frame = view.bounds
        output.isEditable = false
        output.contentInset = UIEdgeInsets(top: 20, left: 0, bottom: 20, right: 0)
        output.autoresizingMask = [.flexibleHeight, .flexibleWidth]
        output.isHidden = true
        view.addSubview(output);
    }

    func sign(_ signIn: GIDSignIn!, didSignInFor user: GIDGoogleUser!,
              withError error: Error!) {
        if let error = error {
            showAlert(title: "Authentication Error", message: error.localizedDescription)
            self.service.authorizer = nil
        } else {
            self.signInButton.isHidden = true
            self.output.isHidden = false
            self.service.authorizer = user.authentication.fetcherAuthorizer()
            fetchChannelResource()
        }
    }


    // List up to 10 files in Drive
    func fetchChannelResource() {
        let query = GTLRYouTubeQuery_ChannelsList.query(withPart: "snippet,statistics")
        query.identifier = "UC_x5XG1OV2P6uZZ5FSM9Ttw"
        // To retrieve data for the current user's channel, comment out the previous
        // line (query.identifier ...) and uncomment the next line (query.mine ...)
        // query.mine = true
        service.executeQuery(query,
                             delegate: self,
                             didFinish: #selector(displayResultWithTicket(ticket:finishedWithObject:error:)))
    }

    // Process the response and display output
    func displayResultWithTicket(
        ticket: GTLRServiceTicket,
        finishedWithObject response : GTLRYouTube_ChannelListResponse,
        error : NSError?) {

        if let error = error {
            showAlert(title: "Error", message: error.localizedDescription)
            return
        }

        var outputText = ""
        if let channels = response.items, !channels.isEmpty {
            let channel = response.items![0]
            let title = channel.snippet!.title
            let description = channel.snippet?.descriptionProperty
            let viewCount = channel.statistics?.viewCount
            outputText += "title: \(title!)\n"
            outputText += "description: \(description!)\n"
            outputText += "view count: \(viewCount!)\n"
        }
        output.text = outputText
    }


    // Helper for showing an alert
    func showAlert(title : String, message: String) {
        let alert = UIAlertController(
            title: title,
            message: message,
            preferredStyle: UIAlertControllerStyle.alert
        )
        let ok = UIAlertAction(
            title: "OK",
            style: UIAlertActionStyle.default,
            handler: nil
        )
        alert.addAction(ok)
        present(alert, animated: true, completion: nil)
    }
}

Step 4: Run the sample

Switch to the QuickstartApp scheme by clicking Product > Scheme > QuickstartApp and run the sample (Cmd+R) using the device simulator or a configured device. The first time you run the sample, it will prompt you to log in to your Google account and authorize access.

It worked!

Great! Check out the further reading section below to learn more.

I got an error

Bummer. Thanks for letting us know and we'll work to fix this quickstart.

Notes

• Authorization information is stored in your Keychain, so subsequent executions will not prompt for authorization.

Further reading

• Google Developers Console help documentation
• Google APIs Client for iOS documentation
• YouTube Data API reference documentation